I'm considering going back to smokeless tobacco because of this sitution. For 400 years, the majority of the population used tobacco/nicotine for increased concentration. Over the last 30 years, that rate has declined, while at the same time, ADHD diagnoses have increased. Studies have shown nicotine is effective in reducing ADHD symptoms, so it seems that society's elimination of nicotine has revealed that it was covering up ADHD for all those years.